This article is from the archive of our partner National Journal

The same-sex marriage debate has long been defined by passion. On the pro-gay marriage end of the spectrum, the most popular argument cites the 14th Amendment's right of equal protection, an often-emotional rationale claiming marriage as a right for all people in committed, loving relationships, regardless of sexual orientation.

But some gay Republicans are striking the emotion from their case for gay marriage. Instead, they're taking a strictly mathematical approach to the Supreme Court to prove how an anti-same-sex marriage decision would curtail another constitutional right: freedom of speech.

Last month, the Liberty Education Forum, the sister think tank to the 30,000-member gay conservative group Log Cabin Republicans, submitted an amicus brief to the Supreme Court in support of a pro-same-sex marriage decision in this year's landmark case, Obergefell v. Hodges, which begins oral arguments April 28. Gay couples who live in states with bans on same-sex marriage face erosion of free speech, the brief contends, because they aren't allowed to give the same campaign contributions as their straight counterparts.

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"If the Supreme Court has been clear about one thing, [it's that] you have a First Amendment right to make a campaign contribution," Craig Engle, Log Cabin's counsel and a partner at Arent Fox, who primarily wrote the brief, told National Journal. "And that from that premise, you cannot treat two similarly situated donors differently."

In the brief, he lays out a hypothetical explaining what Log Cabin calls the "inequity" of the status quo:

"Mr. and Mrs. Brown are a traditional, conservative single-income married couple: He is the breadwinner and she is a stay-at-home mother and wife. They discuss the positions of the candidates and decide they will each make the maximum $5,000 contribution from the husband's income to their incumbent governor. Two people, one household, one income, yet two contributions totaling $10,000 for the governor.

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"Mr. Black and Mr. White are an equally committed single-income couple. Mr. Black works and Mr. White takes care of their adopted children. Their only difference from the Browns is they are not spouses because the state prohibits them from marrying. This couple discusses the candidates and decides to give the maximum contribution they can to the governor's opponent. Two people, one household, one income, but only one $5,000 contribution is allowed to the governor's opponent."

The goal of the argument, says Gregory Angelo, Log Cabin's executive director, was to stand out among a sea of what he figured would be homogeneous briefs based on the equal protection clause—and to make a uniquely Republican case for same-sex marriage legalization.

Log Cabin has used the logic before. Working with Republican candidate Dan Winslow during a 2013 special election for John Kerry's Senate seat, the group asked the Federal Election Commission for clarity on legally married gay couples' rights to both make maximum contributions to a campaign. That year, the FEC determined that "same-sex couples married under state law are 'spouses' for the purpose of" campaign finance regulations.

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This time, the argument was strategically tailored to the high court. Rather than targeting Justice Anthony Kennedy, whom many view as the swing vote in the case, Log Cabin's argument goes for tougher catches: conservatives Antonin Scalia and Clarence Thomas.

"There are several justices on the Supreme Court who would come to mind as not in favor of gay marriage. Yet those are the ones who are the most vigorous First Amendment advocates for campaign finance rights. They are the ones who created Citizens United, they are the ones that created McCutcheon v. FEC, they are the ones who created Davis v. FEC," Engle says, ticking off the landmark recent cases upholding and extending campaign finance rights. "What the brief wants to point out to these justices is, 'If you like campaign contribution rights on Monday, you better also like them on Tuesday.'"

In Angelo's view, if the argument doesn't convince these justices and they rule against same-sex marriage, it would make their subsequent opinions "a tough pill to swallow."

"It would reveal some degree of hypocrisy in the two justices who have been so outspoken on political giving and freedom of speech," he says, "when they have an argument in front of them that shows the very real and quantifiable inequalities that exist for committed same-sex couples on this issue that they have championed for so long."

The strength of the argument, Engle says, rests on its strictly quantifiable (and decidedly unemotional) curtailment of a constitutional right. As long as gay marriage is illegal, the spousal exemption—the portion of the contribution limit law that allows married couples to each donate the maximum amount from one income—does not apply to same-sex couples in states where they cannot be legally married.

Referring to the hypothetical story from the brief, Engle explained that "because Mr. Black and Mr. White are prohibited from being spouses, there you have it: The law has inked in discrimination as clear as can be. And the great thing about this discrimination is it's completely objective. You can do the math."

Even those on the other side of the campaign finance debate say the group makes a good point. John Bonifaz, an attorney and co-founder and president of pro-campaign finance reform group Free Speech for People, says that even though his group does not agree with the notion that campaign contributions qualify as speech, he acknowledges that the current law raises concerns in its "unequal application of the law."

"The current state of the law is such that there is a claimed First Amendment right to make political donations," he says, making sure to note that his group contests that view. "Given that that's the current jurisprudence, it needs to be applied fairly and equally to all. You can't have some people being able to make political donations and others not, who are in the same position."

Ted Olson, the prominent Republican lawyer who successfully overturned California's anti-gay-marriage ban Proposition 8 in a 2013 Supreme Court case, as well as Virginia's ban last year, says that Log Cabin's argument probably won't sway the justices on its own. But alongside the plethora of briefs supporting a pro-same-sex marriage ruling—including his own, filed on behalf of the clients he represented in California and Virginia—it could boost the broader case for legalization.

"In the context of patterns of discrimination, that's certainly important to be able to have the same forceful voice," he says. "And if you are restricted with respect to financing your point of view in an election process, that's reducing the force of your voice because of your sexual orientation."

For a court that has repeatedly ruled that campaign contributions are a way to express free speech, it could be a convincing argument.

This article is from the archive of our partner National Journal.

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